The Reduction of Heat Losses to the Diesel Engine Cooling System

The benefits of applying thermal insulation to the exhaust ports and combustion chamber components are predicted using a computer simulation of a highly rated turbocharged DI diesel truck engine. Comparisons are made between a standard engine and engines with the exhaust port, cylinder head, piston and cylinder liner insulated individually or in combination. The necessity of re-optimizing engine conditions when heat losses through the combustion chamber walls are significantly changed is also examined.

The importance is recognized of developing techniques of reducing heat losses to the engine cooling system which can be applied at low cost and with minimal changes to existing engine designs. Potential methods of achieving these objectives are reviewed and their effectiveness assessed.

This paper also describes the successful testing of a ceramic liner located in the exhaust duct of a diesel engine during more than 1000 hours of engine operation.